Drilling mechanism



Sept. 18, 1928.

T. R. E. RUNDQVIST DRILLING MECHANISM Filed March 13, 1924 4 R. @CMM sv.su

Cil

Patented Sept. 18, 1928i.

vUNITED STATES PATENT OFFICE.

THORE R. E. RUNDQVIST, 0F CLAREMONT, NEW HAMPSHIRE, ASSIGNOBl TOSULLIVAN MACHINERY COMPANY, A CORPORATION 0F MASSACHUSETTS.

DRILLING MECHANISM.

Application led March 13, 1924. Serial No. 699,111. A'

I'lhis invention relates tov drilling mechanisms.

It has for its object to provide an improved drilling mechanism. Afurther object is to provide a drilling mechanism having an improvedfeeding means with improved means [or controlling the flow of fluid tothe feeding mechanism. A further object is to provide improved feedcontrol means particularly adapted for a spotting operation. It is afurther object to provide an improved feed control mechanism that willautomatically hold the drilling mechanism'in substantially a stationaryor balanced condition. It is a further object of my invention to providesuch a controlling means for the feeding mechanism which employs apiston having differential areas so that the forward feeding force willbe just sufficient tozhold the steel in a spotting positionl against therecoil of the drilling motor.

Y In the accompanying drawings I have shown for purposes of illustrationone form which my invention may assume in practice.

In these drawings,-

Fig. 1 is a side elevation partially broken away to show details ofconstruction.

Fig. 2 is a diagrammatic view of my improved control means forsubstantially balancing the feed.

Fig. 3 is a transverse vertical sectional view taken substantially online 3-3 of Fig. 1.

Fig. 4 is a detail sectional view of the valve 30 shown in Fig. 2 withthe valve in a different position.

Fig. 5 is a detail sectional view of the control valve 10 illustratingthe connection of the forward and reverse feeding passages.

In the illustrative form of my invention it is shown as embodied in adrifter type of drill comprising a combined feed cylinder and support 1having a depending member 2 adapted to be engaged by any suitablesupport and having longitudinal guideways 3 disposed on the upper sidethereof Within which is slidably mounted a drilling mechanism 4. Thismechanism comprises a usual percussive motor cylinder 6 having a. chuckhousing 7 mounted thereon and adapted to carry a Steel 8 while a4 rearcylinder head 9 carries a usual pressure fluid control valve 10 havingcommunication with a main fluid passage 11 leading to a fluiddistribution valve 12 for the motor 6v.'v

The feeding mechanism of my improved device comprises an arm 13projecting rearwardly from the lower side ofthe head 9 and terminatingin'depending members 1'4 and 15 which carry at their lower. -end a. boss16 having a conical bore 17 within which a plug 18 `is disposed and heldtherein 'by a nut 19. 'lfhreadedly connected to reduced portion 20of theplugf18` is'ahollow'piston lrod 21 projecting fc rwardly t'hou' h acombined rearv cylinderfhead and packing member 22. Mounted upon theforward end of the rod 21 is a .piston 23 held thereto as by a hollownut 24. Also. carried by the member 18 is a fluid conducting tube 26whichprojects forwardly fromja chamber 27 and terminates. in 4a head 28adjacent. thenut 24."

In order that the drilling mechanism 4 may be held to its spottingposition independently of the main control valve 10, I have provided thefollowing mechanism comprising a balancing valve 29 controlled by'amanual valve 30. The objectv of the balancing valve is to substantiallyequalize the rearward and forward feeding forces so that the feedingmechanism may, according to the proportions given my balancing valve,either be held in a complete balanced condition or given a slightforward feeding force just sufficient to overcome the recoil of thehammer piston disposed within the cylinder 6 and thereby hold the steelin spotting position at the working face. My improved balancing valve,also must have embodied therein means for not only balancing the fluidpressure'forces acting on the pressure areas of the feed piston, butalso balancing the weight of the drilling mechanism when the same isdisposed in an inclined position. More specifically', this valvecomprises an enlarged central portion 31 disposed in a bore 32 andhavingoutwardly projeeting piston members 33 and 34 reciprocably mountedwithinbores 35 and 36 respectively. Said central portion has spacedannular grooves 37 and 38 communicating respectively with the bores 35and 36 as by passages 39 and 40 in the valve 29, while passages 41 and42 and small vent ports 41 and 42a allow communication between the bores35 and its for wird2 p'ositn, live pressure fiiiid is admitted to thefr''iitff piston 23 as by: apas-A sage 43 leading from the main valvel0, an annular groove 44 formed on thep'eiiphe'ry of the valve 30, apassage 4 5, groove4 3T, passage 39 to the. `bore 35, outa 'passageana'niiikilarYroovefalso formed on theperiphery of t4 eval e30,tli'rough'a' pziss'ige'etS and 'i groove formed the'valv'eBOintermediate the; s 44; and- 47, 'passage 5I leading t'oi the hollowbore o f pisto'ni'rd I2 1 port 52 foi thefrear -sidel of. the Apiston23. 1t will liliribe'Ii'Qt'edithatA Wliiithe 'Valve 29 ,is in a positionopposite from that slioivn' in'Figf2 the here fof the .cylinder attliefront side of the piston is ventedlto, atmosphere byfvaypf passages 48and 4 6,- -groove 37 thevalve29, and exhz'rii'stl passaf ie `42 `Inorder 'to allow free n'iovelrient off the valve 29 botliiendsA f bore32am vented' to atmosphere as bythe 41a l and 42" eoininu'riieatii'icr\\'i th l'the exhaust passzrges 4l and A2, resp'el ely This position ofthe valX-*e 30is maintained by the operator merely pressingv the button54 against the'tension Vofa spring It )vill lie stated: heretliatinasiniieli'as-it is' the prirposeoffthe balancing valve 2S) to`maintain substantially'eqiial' forces on each side' of 'the piston 23,the effective pressure areas oi'itlie 'ends of the pils-tons 33, 3fthaving the saine proportion to theiveight of this valve as theCorrespondingpressure areason the Afeed pist0n 23 have to the 'Weight ofthe tool'actiiatimg motor and the parts ot the meehan'ism movabletherewith.

*Inthe operation of the device thus fardeseribed. ifitis desired to spotthe hole, tlie vaflveBO will be pushed to the position shown in'Fig'..2in vvhich ease pressure fluid will flow from the controlvalve 10through thepassige 4 5' to the end of bore and to the torivard side ofpistori23 and When the pressure on that side of the piston builds up,say to a pressure less thanV line pressure. this pressure'acting uponthe forward effective area of the piston 23 Will throiv valve 29 toitsolther position. Said hore 35 is then' immediately vented to theatmosphere th rough groove 37 in the valve 29 and exhaust passage 42,but the' passage 4G is of sutlieient length to take a considerable timeto wholly relieve the pressure in front of the piston 23 and, as willbepresently seen, the valve 29 travelsfastenough so that a substantiallyconstant pressure will be niain tained in the feed cylinder atall times.It vill' bel -un'derstood thatlt-'lie"ielativelyslig'lit iitietiiati'not thev`v valve r29," here-iii' between the liinits of 5th to ygth of aninch, has no ina- `"terz'il zrf'e'et" on the pressure in the feedcylpressure flu idl through" 45,;xt0 the annular groove 37 fthe valve"29 and will also eut off Apass agg-*es 46faiid49 ledd'in'g' 'to theends of pistons 33aiid thi-'is wholly et'ittiigo'iit the operation otsaid balancing valve,-

iiular-rrooves' 47`ai'id'50 formed in the periph-` civsja'rieeof mepiston 3i vice EWill be apparent-from' the foregoing de'- scription inconneetienwvitlhthe balancing improved balancing valve the operatorneeds only to pressi-the button 54 whereby" the feed Or'tl-iedrilfling'mechanism ivil'l be suitable' for'sp'otting conditions and=doesnotrequire the operator' to Iirstftlu'ov: 'the' mai-n controlf valve rnone direction to obtain a fmfivard'v feedfandthen in the reversevdirection to obtain a reverse'feedlin order to counteract-the fullforward feeding,y force. 'Vhentlie}drill is in anj inclined positionI'there will begaf tendency'-for-tlie drill dueto its'weight-'to slldefbackor foi. ivai'd, depending uponf-the direction' ofinlination v'of'theV drillf. This* necessitates: a greater pressure on'- the-side of thepiston, in which direction Athe 'mechanism tends'fto'lslide, t'o'holdthe drill -in` a balanced conditi-oni: This is accomplishedby making theWeight'of the valve 29 in proportion to the' weigh'to'f theinovalilezpartofthe drilling 'mechanism'. If the drill' is inclined the'presl sure; on the vsmall area 3ft-necessary to move" the-valve29i'ivill antomatically `be--increased' for'gt'lie'valve will Tema-iiiin its lower` posi'- tion-uriti'l the' pressure builds up in the feed'cylinder; i' O'f Acourse during this operation' the rangeo'f pressure atthe 'ends of thevalve 29 -issiich1 thatiline pressure isne'\-'er-attained thereby leaving an excess pressure to'be used whenltl`1e"".lr ill isf inclined- T'Vhill have inthis-application'specifically' modied ndernhodied invarious other formswithoutdeparting l of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

r from its spirit or the scope 1. A. drill mechanism comprising a toolactuating motor.v feeding means therefor includingl relatively movableelements, means including a valve to subject one of said ele ments toopposing fluid pressure created forces .for automatically maintainingsaid feeding means in a substantially balanced condition, said valvemoving oppositcly automatically in accordance with variations in saidforces to control the supplies of fluid which produce said forces, andmeans including a valve operable at the will of the operator forcontrolling said automatic means.

2. A drill mechanism comprising a tool actuating motor, feeding meanstherefor including relatively movable elements`r means including a valveto subject one of said ele- 'tions in' said cyli nder,i titel pressurelare-.asini -said Ivalve yhaving thj'eJ 'sameproportintd t I' pressureareas on' said'lpi'sto'have tli ments to opposing. fluidi-pressurecreated forces for automatically maintaining saldi feeding means in asubstantialliy balanced condition to reduce- -th'ewonlrperforxnance'-`thereof', said v-a'lve fmoizing 'oppsi't'ely auto; 57o? matically inaccordance 'i'vitll variations' in vSaid forces to @entrambe suppliesiorfluid:

inga valveoperable -to Tender said'atoil'ialic' means inoperative to'allow said feedingm'eans; 73" to normally operate.A i3: `A drilli'mech`anism comprising. a tol actuating motor, pressure fluid actuated'feed' ing .means therefon comprising' la feed cylinton= having. dierential'pr'essure areas, andiw means including a valveArespensive'toIpresi-'j sure conditions' Wflthirr said feed'eylmderiandl havingpressure2. areas proportionai to! said vdi lferentiial' piston i areas for.;controllingfi the; 'S355A flow lof fluid to said -Ifee'd cylinder'. i

A Idrinnuechani'smcomprising i jimi: actuating imotorg p res'sunel fluidactuated "fe'ed'l t Y ing vmeans therefor comprising a; feed cylinder--and al feed pistonfthere saidi'f'ee'd pi'ston9W having differentialpressu' l aleals'gfandmeansfor controlling-flnidflivtlszidcyllndeicludinga' valve responsive to pressure condi-"- weight yof saidfivalvefas the'. 'cor-iespend' Weight of said.'tool'factliztiii'ginotoriidthe" p arts of the mechanism 2 movable-therewith.

5. A drill mechanism co'm'p'ri''sil'igi-al*tooli100:;4

actuatingr moto'r,pressurefflu-idtetatd ffe'ed ing means therefor'comprisinga fe'edcylinderand a feed: :piston -therein,-s aid pistonhaving-f.' d itl' e rential pressure areas, and iniiris -in'el'u'di inga valve responsivetopressur cond-itin i with-in saidv feed cylinder'an'di'ifavin'gpress'i'ireAA areas proportionalto' sa-iddiflerentia-lpistonareas for-controlling flowof==flhid to said cylinder toVau'tomaticallyl maitain-si-b'st'ar# tillj.j equalopposing"freesthereon.-

(i. A drill mechanism comprising-vv work performing means for actuatinga drill steel, pressure fluid actuated forward and reverse feeding meanstherefor including a piston, and means comprising a directly fluidactuated valve operable independently of said piston and responsive topressure changes in said feeding means for automatically maintainingsaid feeding means in a substantially balanced condition during spottingof a hole.

7. A drill mechanism comprising a motor for actuating a drill steel,pressure fluid actuated feeding means therefor including a feed pistonhaving opposed differential pressure areas, and means comprising a valveresponsive to pressure conditions in said feeding means and havingopposed differential pressure areas proportional to the areas of saidpiston, said means being effective for automatically maintaining saidfeeding means in a substantially balanced condition.

8. In a drill mechanism comprising work performing means, pressure fiuidactuated feeding means therefor comprising a cylinder and a cooperatin,fY piston, and means independent of said piston and responsive topressure changes in the ends of said cylinder at opposite sides of saidpiston for automati-- for actuating a drill steel, pressure fluidactuated feeding means therefor including a piston, a main throttlevalve for controlling said motor and feeding means, means comprising adirectly fluid actuated valve independent of said piston -and responsiveto' pressure changes in said feeding means for automatically maintainingsaid feeding means in a substantially balanced condition, and manuallyoperable valve means for con trolling the fluid flow between said mainvalve and said automatic valve.

11. A drill mechanism comprising a inotor for actuating a drill-steel,pressure fluid actuated feeding means therefor including a piston, amain throttle valve for controlling said motor and feeding means, meanscomprising a directly-fluid actuated valve independent of said pistonand responsive to pressure. changes in said feeding means forautomatically maintaining said feeding means in a substantially balancedcondition, and manually operable v alve means to cut out said automaticmeans during normal feeding of the motor.

12. A drill mechanism comprising a inotor, pressure fluid actuatedfeeding meansing means in a substantially balanced condition.

13. A drill mechanism comprising a tool actuating motor,.pressure fluidactuated feedif ing means therefor comprising a feed cylinder and a feedpiston therein, said'feed piston having differential pressure areas, andmeans for maintaining said feeding means iii a substantially balancedcondition including a valve responsive to pressureA conditions in;V

said cylinder, thepressure areas on said valve having the sameproportion to the weight of said valve as the corresponding pressureareas on said piston have to the jweight of said tool vactuating motorand the parts of the ymechanism movable therewith.

14. A drill mechanism kcomprising Work performing means, pressure fluidactuated; feeding means thereforcomprising a cylinder and a cooperatingpiston, and means comprising a valve responsiveto pressure changes insaid feeding means for automatically alternately connecting the ends ofsaid cylin-I der atopposite sides of said piston to suply and exhaustfor maintaining said fee ing means .in a substantially balanced'condition. l5. A drill mechanism comprising vwork performing means,pressure fluid actuatedI feeding means therefor including a piston,

and means comprising a valve independent of said piston and havingopposed differential pressure areas subjected lto pressure changes insaid feeding means for automatically maintaining said feeding means in asubstantially balanced condition.

In testimony whereof I affix my signature.

TiioaE a. E. RUNDQvisT.

